Electric-arc lamp.



Patented Deu;L I2, |899.

J. J. WOOD.

ELECTRIC ABC LAMP.

(Application led Aug. 25, 189B.)

3 Sheets-Sheet l.

(No Model.)

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No. 638,789. Patented Dec. l2, |899.

J. J. WOOD.

ELECTRIC ARC LAMP.

(Application filed Aug. 25, 1898.) (No Modem 3 Sheets- Sheet 2.

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No. 638,789. Patented Dec. I2, |899.

J. J. WOOD.

ELECTRIC ARC LAMP.

(Application filed Aug. 25, 189B.)

3 Sheets-Sheet 3.

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WITNESSES:

1 ucmms versus cu mor UNITED STATES PATENT OFFICE.

JAMES J. WOOD, OF FORT WAYNE, INDIANA, AssIcNoR To THE GENERAL ELECTRICCOMPANY, OF NEW YORK.

ELECTRIC-Ano LAt/IaI SPECIFICATION forming part of Letters Patent No.638,789, dated December 12, 1899.

Application tiled August 25,1898. Serial No. 689,470. (No model.)

T0 @ZZ whom it may conceive:

Be it known that l, JAMES J. lVOOD, a citizen of the United States,residing in'Fort lVayne, in the county of Allen and State of Indiana,have invented certain new and useful Improvements in Arc-Lamps, of whichthe following is a specification.

This invention relates to arc-lamps designed principally for alternatingcurrents, although containing` improvements applicable also todirect-currentlamps. The improvements relate to the feed mechanism, thedash-pot, the switch, and the regulating-magnet.

One object of my invention is to adapt a clutch-feed mechanism to analternating-cur rent lamp. Prior to myinvention it has been necessary toconstruct alternating` current lamps with a geanfeed. All attempts tomake a clutch-feed mechanism operate in an alterhating-current lamp havebeen unsuccess ful, for the reason that the alternations of the currentset up a vibration in the mechanism, causing the feed-rod to graduallyslip through the clutch, so as to feed the carbons together prematurely.By my invention l suspend the armature or movable member of theregulating electromagnct or solenoid in such manner that its vibrationsare not transmit-ted to the clutch, While its bodily movements under thecontrol of the magnet are effectivelytransmitted to such effect that themechanism acts in the same manner as though the magnet were traversed bya direct current. This I accomplish by supporting the armature in thearmature-lever on springs Which act at right angles to the direction ofmovement of the armature, so that the vibration transmitted to thearmature by the alternating current loses itself in the springs and isnot transmitted through them to the armature-lever. The springs aresufticiently stift' so that when the armature is moved bodily they pullthe lever with it, and thereby draw the arc. The springs might beinterposed at any point in the mechanism between the armature atoneeXtreme and the clutch at the other.

Iwill proceed to describe my invention with reference to theaccompanying drawings, which show one embodiment thereof.

Figure 'l is a vertical mid-section through the mechanism-case in theplane of thelinel l in Figs. 3 and O. Fig. 2 is a vertical sectionthrough the mechanism-case in the plane of the line 2 2 in Fig. Fig. 8is a horizontal section in the plane of the line 3 3 in Fig. 2. Fig. 4is an elevation of the mechanism, the case being in section in the sameplane as Fig. l, the view looking in the contrary direction thereto.Fig. 5 is a horizontal section in the plane of the line 5 5 in Fig. Al.Fig. 6 is a frc gment of Fig. 4.-. Fig. 7 is adiagrammatic elevation ofFig. G. Figs. S and 9 are views on a larger scale than the preceding,Fig. 9 being a plan of the top plate of the mechanism-case, and Fig. 8 avertical section of the top portion thereof in the planes indicated bythe line 8 in Fig. 9. Fig. lO shows thethree members of the switch-armseparated. Fig. ll shows them assembled and shows the act of unitingthem. Fig. l2 is a vertical section of the dash-pot. Fig. i3 is ahorizontal section thereof, showing the plunger in plan. Fig. li is avertical mid-section of one of the magnet-spools. Fig. l5 isa plan ofthe punching from which the magnetspool bracket is bent. Fig. 16 showsan edge and plan view of this bracket.

Referring to the drawings, let A designate the mechanism-case; B,theframe supporting the mechanism; C, theglobe; D, the feed-rod, which, asusual, carries the upper carbon, and E E the side rods,which, asusual,extend down within the globe and carry the lower carbon.

M is the regulating electromagnet or solenoid, the movable member orarmature m of which is connected to the armature-lever F. This lever ispivoted at ay a and is connected by a link Z9 to a clutch-lever G, whichmay conveniently be arranged above it and to which is pivoted in theordinary manner the clutclrsleeve H, which surrounds the rod D, and atone side of which is the clutch-shoe c, pivoted between two arms d,projecting into the annular portion of the lever G in the well-knownmanner. There is nothing new in this clutch, which is one commonlyapplied to continuous-current lamps. As the end of the lever G is raisedby upward pressure through the link b it tilts this leverand presses theshoe c against one side of the rod, While drawing the sleeve Il againstthe other side IOO thereof, so that the rod is firmly gripped betweenthe sleeve and shoe, and consequently is lifted with the lever G. As thelever is lowered by the weakening of the magnet M the downwardly-turnedend or tail e of the lever strikes an arm e on the lever F, (or it mightstrike a fixed abutment,) so that the further lowering ot' the oppositeend of the lever G by the link l) releases the clutch and permits therod D to slide down through it. The lever F has an arm f, which projectsbeyond the armature, and the end of which is connected in t-he usualmanner to the stem g of dash-pot I. This clutch mechanism is not hereinclaimed, being claimed in my pending application, SerialNo. 687,119,tiled July 28, 1898.

The electromagnet M may be variously constructed but it is preferable toemploy a magnet of the solenoid type having its armature formed of alill-shaped core built up of iron laminae, with its opposite legsinserted in the respective solenoid-coils.

The armature m is connected to the armature-lever F through the mediumof springs s s, which constitute the sole connection between thearmature and lever and are adapted to take up or absorb any vibration ortrembling of the armature by reason of the eurrent alternations, so asto avoid transmitting` such vibration to the lever. This is preferablyaccomplished by two oppositely-acting or reciprocal springs pullingequally against each other in a direction perpendicular to the directionof movement or vibration of the armature, or, in other words, at rightangles to the direction of pull of the electromagnet. Preferably thesprings are coiled or helical springs, although this is not essential.Preferably the lever F is widely bifureated adjacent to the armature bymeans of the arms 7i h, whichextend laterally parallel with the armatureand considerably beyond it, terminating in outwardly-turned pins orhooks it', with which one end ot each spring is connected, while theopposite end of the spring` is joined to an eyej, screwed or otherwiseunited to the armature. The springs may, however, be very differentlyarranged in connection with different constructions of armature andlever without departing from my invention. The essential action of thesprings is indicated in the diagram Fig. 7, in which, however, theamplitude of the vibration of the armature is greatly exaggerated. Infact the vibratory movement ot' the armature which occurs in verticaldirection is so slight as to be almost or quite imperceptible. Theamplitude of vibration is represented in this diagram by the dots a* x.The vibratory movement carries the ends of the springs which areattached to the armature up and down along the vertical linesintersecting these dots. The opposite ends of the springs, which areattached at t t' to the lever, constitute practically ixed points, thevibration being essi/e9 taken up by the lateral swing or ilexure of thesprings around these points. The springs exert a strong pull outwardlyagainst the armature and tend to return the armature to midposition. Thevibratory movements of the armature, being exceedingly minute, do notmaterially elongate the springs, and as the vibrations occur equally toopposite sides of the medial line each opposite semivibrationneutralizes the other before a diagonal pull can be communicated throughthe springsto displace the armature-lever, a result to which the inertiaof the lever contributes. When, however, the armature, in addition toits vibratory movement, is moved bodily up or down, an unbalancedoblique pull is thereby communicated through the springs s s, distending these springs and causing them to exert tension in upward ordownward direction against the armaturelever, which accordingly followsthe bodily movement of the armature.

Practical use of the feed mechanism thus described has demonstrated thatthe clutch is uninfluenced by the vibration of the armature. With theusual unyielding pivotal connection between the armature and lever whenused in au alternating-current lamp the vibrations ot the armature arecommunicated through the lever to the clutch, the entire feed mechanismbeing subjected to suchconstant vibration or trembling as to cause thefeed rod to continually slip through the clutch, thereby bringing thecai-bons prematurely together. This result has practically ocndem nedthe use of clutch-feed mechanisms for alternating-current lamps, forwhich the relatively-complicated gear-feeds have heretofore had to besubstituted. My invention greatly simplifies and cheapens the feedmechanisms of alternating-currentlamps by enabling the use of a clutchfeed.

Another feature ot my invention relates to the construction and mountingof the magnet for altemating-current lamps. In such lamps ordinarily themagnet-spools on which the wire is wound are usually made of metal, andin order to reduce to a minimum the currents generated in the spools,and consequently the heat, the spools are ordinarily split. This,however, does not entirely avoid the loss, although it greatly reducesit. By my present invention I make the magnetspools 7.; 7c of insulatingmaterial, one being shown in section in Fig. it. This enables them to bemade without any split and avoids all internal or induced currents, suchas are caused in a metallic spool. Instead of fastening the spool at oneend only, as heretofore, I Afasten it at both ends. In the upper end ofthe spool is inserted a metal nut Z, preferably conical, as shown, and ascrew l is put through the top plate p' ot the mechanism-frame B andscrewed into the nut Z. For

bracing the lower end of the spool I provide a bracket J', (shown inFig. 16,) which is IOO assise formed by bending up a punching J of theshape shown in Fig. 15 and which is bent on the dotted lines therein, so'as to form a perforated base n by which to fasten it, and a bracketportion n, projecting beneath the lower head of the spool and bifurcatedto leave the central bore of the spool unobstructed, and with threefingers n2, turned up to partly embrace the bottom iiange of the spool.These brackets J are shown in place in Figs. 2, 3, and 4. Their baseportions n are fastened by screws to the two upright walls p p of themechanism-frame B.

The dash-pot I is made, preferably, tifty per cent. larger in diameterthan usual, and its piston is made a loose tit to prevent sticking. Thedash-pot is provided with an inwardly-opening check-valve adapted toremain closed during the upward or arc-drawing movement, but to open oradmit air during the downward orV feeding movement. I prefer to havethis check-valve carried by the piston or plunger, but it may beotherwise arranged. In Figs. 12 and 13, q is the dash-pot cylinder, and7^ the piston or plunger. The latter is formed of an eXternally-groovedtube with a disk forced tightly into it, to which the stem g is secured.On the metal disk lies a valve-disk r', of leather or other flexiblematerial, which is fastened on at one side by a screw, and the other orfree edge of which is weighted by a lead button directly over anair-hole t. During the upward movement the leather disk r closes thehole t and prevents escape of air from above the piston, except as theairslowly leaks around it. During the downward movement the valve-diskr' is free to lift, permitting air to pass up through the hole t. Thedash-pot thus resists the upward or arc-drawing movement and moderatesthis to a suitable slow movement, while it affords comparatively littlere'- sistance to the downward feeding movement, thereby admitting of aquick feed.

My invention also provides an improved construction of switch applicableto either continuous or alternating current arc-lamps. Themechanism-frame Bis, as usual, included as part of the circuit leadingfrom the switch to the feed-rod D and is insulated from the top andbottom plates u and t, respectively, of the mechanism-case. Theleading-in wire tu, which enters at the top of the lamp, as usual, andpasses down between the outer shell and the suspension-tube or feed-rodhousing u', terminates in one member of the switch, while the othermember is mounted on the top plate p of the mechanism-frame B, so as tomake electrical connection therewith. Preferably it is the movablemember of the switch which makes connection with the end of the wire w,this member being mounted on the top plate u. Referring to Figs. 8 tol0, the switch is preferably constructed with an oscillating post 10,turning in an upwardlyprojecting boss 11, formed on the plate u andhaving pinned to it an arm 12, which carries an insulated contact-head13. The post 10 has a head at its lower end which prevents its lifting,while the arm 12 restrains its downward movement. It is prolongedupwardly through a hole 14C in the sheet-metal shell or cap y, whichincloses the top of the mechanism-case, and on its protruding upper endis fixed an arm 15, which may be attached by means of a set-screw 1G,the arm carrying a handle 17 preferably of insulating material. The bossof the arm 15 is formed as an inverted cup which caps over the top ofthe post 10. The lower part of this cup is counterbored or enlarged,forming an annular iiange. The margin of the hole 14 is upturned andprojects within the flange of said cup, so that the latter incloses itand serves to prevent the entrance of rain. The contact-head 13 is ofmetal, and the end of the leading-in wire w is soldered into a hole inits side. The head 13 is united mechanically to the arm 12, whileinsulated therefrom, by constructing the one of these parts with areduced neck or shank 13 and the other with a socket 19 with thin wallsand providing a sleeve 2O of insulating material, preferably mica, toiit between them. The three parts are then united, as shown in Fig'. 11,by thrustingthe sleeve into the socket and forcing the shank into thesleeve, the insulating-sleeve being long enough to prevent metalliccontact between the parts 18 and 19. The shank is notched on oppositesides, as shown at 21 in Fig. 10, and the parts are finally united byindenting the walls ot the socket 19 at points coincident with thesenotches by applying pressure from opposite sides--as, for example, bymeans of two mutually-approaching jaws or parts .e 5, Fig. 11. Theresult of this indentation of the socket is to crimp theinsulating-sleeve into the notches in the mannerclearlyshownin Fig. 8.Thisconstruction admits of an insulation of mica, thereby rendering theswitch fireproof. I prefer to make the socket 19 of brass and as part ofthe arm 12, and to make the shank 18 integral with the head 13. I preferalso to make the shank and socket slightly conical, as shown in Fig. 10,so that the parts can be forced together to make a tight iit. Theindenting of the socket into the notches effects a very firm andpermanent union between the respective parts. The contact-head 13, withthe arm which carries it,constitutes the movable member of the switch.Its stationary member is constituted by a rocking contact-shoe 22, whichis pivoted on a stud 23, screwed into the top plate p' of themechanism-frame B and having a spring 24 tending to press it constantlyagainst a stop 25, projecting from the plate p. The post 23 and stop 25project up through a large hole in the top plate u, so as to avoidmetallic contact with the latter. The shoe 22 has a cam-face on the sidenext IOO IIO

scarse the head 13, which comprises a recess 26 for receiving the end ofsaid arm when the switch is fully closed, in which position the tensionof the spring 24: presses the shoe against the head in such manner as toretain the latter in said recess, so that to open the switch it isnecessary to apply force to the operatinghandle 17 to cause the head 13to deflect the shoe 22 while escaping from said recess'. The movement ofthe arm 12 in opening the switch is limited by a stop 27, consisting ofan npwardly-projecting lug on the top plate u. The wire w is looped andsufficiently long to permit it to yield in following` the movements ofthe arm.

I claim as my invention the following defined novel features,substantially as hereinbefore specified, namely:

l. In an arc-lamp for alternating currents, the combination with thefeed mechanism and regulating-magnet, of a 'yielding medium interposedbetween the movable member of said magnet and said feed mechanism,adapted to communicate the bodily movements of said member whilesuppressing' the communication ofits vibration, and consisting of aspring arranged to exert stress perpendicularly to the direction ofmotion.

2. In an arclamp for alternating currents, the combination with aclutch-feed mechanism and the regulating-magnet, of means interposedbetween the movable member of said magnet and the clutch, adapted tocommunicate the bodily movements of said member while suppressing thecommunication of its vibration, and consisting of a spring arranged toexert stress perpendicularly to the direction of motion.

3. In an arc-lamp for alternating currents, the combination with thefeed mechanism, the regulating-magnet and the armature-lever, of aspring interposed between the armature and said lever, arranged to exertstress perpendicularly to the direction of movement, and hence adaptedto communicate the bodily movements of said armature while suppressingthe communication of its vibration.

Lt. In an arc-lamp for alternating` currents, the combination with theregulating-magnet, its armature and armature-lever, of interposedsprings arranged to exert stress perpendicularly to the direction ofmovement of the armature.

5. In an arc-lamp for alternating currents, the combination with theregulating-magnet, its armature and armature-lever, of opposite springsconnecting the armature and lever, arranged to pull against each otherin a direction perpendicularly to the movement of the armature.

6. In an arc-lamp for alternating currents, the combination with theregulating-magnet M, its armature m, and armature-lever F formed witharms 7L 7L, of springs s s interposed between the arms of said lever andthe armature and arranged to pull against each other in a directionperpendicularly to the movement of the armature.

7. In an arc-lamp for alternating currents, the combination with themechanism-frame of the regulating-magnet, the latter having its coilswound on spools of insulating material, the upper ends of said spoolshaving countersunk nuts fastened to the top plate of the mechanism frameby screws passing through said top plate and entering into said nuts.

S. In an are-lamp for alternating currents, the combination of themechanism-frame, the regulating-magnet, the latter having its coilswound on spools of insulating material, the upper ends of said spoolsfastened to the top plate of the mechanism-case, and brackets fastenedto said case and engaging the lower ends of said spools.

9. In an arc-lamp for alternating currents, the combination of themechanism frame having top and bottom plates and intervening luprights,the regulating-magnet, the latter having its coils wound on spools ofinsulating material, the upper ends of said spools fastened to said topplate, and brackets fastened to said nprights and having bifurcatedportions extending therefrom beneath the lower ends of the respectivespools, and each formed with upturned fingers engaging and centering theend of the spool.

lO. In an arc-lamp for alternating currents, the combination of themechanism frame, having top and bottom plates and intervening uprights,the regulating-magnet, the latter having its coils wound on spools ofinsulating material, the Lipper ends of said spools having countersunknuts fastened to the said top plate by screws passing through the topplate and entering said nuts, and brackets fastened to said uprights andengaging the lower ends of said spools.

11. In an arc-lamp, a switch comprising a swinging contactarm, a rockingcontact-shoe against which said arm rubs in closing or opening theswitch, said arm and shoe forining the respective circuit-terminals,said shoe having a camface comprising a recess for rcceiving the end ofsaid arm when the switch is fully closed, and a spring pressing againstsaid shoe to resist its deflection during the movement of the arm to theopen position, whereby the conducting contact-surfaces are held firmlyseated together while the switch is closed.

12. In an arc-lamp, a switch comprising a swinging arm, and an insulatedcontact-head carried thereby, said arm and head formed the one with anotched shank and the other with a socket, with an interposedinsulatingsleeve, the socket indented opposite the notch in the shank tocrimp the insulation thereinto and hold the parts firmly together.

13. In an arc-lamp, a switch comprising a IOO IIO

IIS

swinging arm, and an insulated contact-head In witness whereof I havehereunto signed carried thereby, said arm and head formed my name' inthe presence of two subscribing ro the one With a conical notched shankand the Witnesses.

other With a socket, with an interposed insulating-sleeve, the shankbeing forced into the JAMES J' TOOD socket and the latter indentedopposite the Witnesses: notch n the shank to crimp the insulation ROBERTXV. SMYTH, thereinto. A. L. HADLEY.

